“story grid” for editors, what is of particular interest to me is the recurrence
of self-similar patterns in well-written
fiction. Snowflakes consist of fractals,
and Coyne has identified similar patterns in well-written novels repeating
in sub-scenes he calls “beats” and in
scenes, scene sequences, and even the
Aristotelian three-act structure; that
is, same pattern, different scales. The
“story grid” method performs a quantitative dissection of fiction, allowing
editors to help create generally engaging fiction.

Fractals, or mathematical sets
repeating at multiple scales, appear
frequently in nature. Examples range
from Romanesco broccoli to river
basins and ferns. Prominent identification of fractal-related scholarly
work includes the Mandelbrot set,
Serpinski’s carpet, Koch Snowflake,
Julia set, strange attractor, and unified mass central triangle. We can
thus infer well-written works of fiction might be better modeled through
a combination of formal specification
and fractals. Formalism could thus be
useful even for people associated with
the novel-publishing industry.

No Hologram from HoloLensAlthough Marina Krakovsky’s newsarticle “Bringing Holography toLight” (Oct. 2016) was timely (thevisual interface will indeed dominatethe future), the photo in the article’sFigure 1 above the caption “Learningmedicine in three dimensions withMicrosoft’s HoloLens.” was com-pletely opposite of what Krakovskysaid in the article’s opening sen-tence. Microsoft HoloLens is not evendesigned to produce a holographicimage. On the contrary, MicrosoftHoloLens is just a see-through ste-reoscopic head-mounted display,with two diffractive mirrors that areprefabricated diffractive reflectionlenses manufactured either by dia-mond turning or optical holography.There is neither holographic process-ing nor holographic image recon-struction. In the HoloLens, a stereo-scopic image pair is projected beforethe user’s eyes through the diffractivemirrors. There is a marked differencebetween a stereoscopic 3D image anda holographic image. A holographicimage can reproduce true 3D perspec-tives, whereas a stereoscopic 3D im-age cannot.Debesh Choudhury, Kolkata,West Bengal, India

Why Not Trisexuality?

Adi Livnat and Christos Papadimitrioureview article “Sex as an Algorithm”(Nov. 2016) was fascinating but mis-titled. It discussed the benefits ofconjugality. George C. Williams inSex and Evolution distinguished themore general concept conjugality from(eu)sexuality, in which the numberof conjugal strains in the species isequal to the number of individualsparticipating in conjugation—two,in all conjugal species on this planet.This seems an important distinction,and I suggest the cover of Communi-cations was misleading. In my ownbook Albatross I emphasized thisand other distinctions, aiming toavoid nonsensical talk, as in thatarising from “the gostak distims thedoshes” in The Meaning of Meaning byC.K. Ogden and I.A. Richards.Livnat’s and Papadimitriou’s refer-ence to their non-coverage of hetero-zygosity was revealing. I rather suspectheterozygosity is a prerequisite forsexuality proper; certainly a lot of sex-ual species are haploid in the gameticgeneration and diploid in the others.Some of the mathematics as to thebinarity of conjugation might be in-teresting. What are the chances thaton some other world there may haveevolved life with a triple helix, ternaryconjugation—and so trisexuality?John A. Wills, Oakland, CA

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